Size gauge



May 2, 1944. I F, MOORE 2,348,018-

- 'sIzE GAUGE Filed March 31, 1942 X Jaw/2W g, M? Iii/@0749 Patented May 2, 1944 .1

UNITED STATES SIZE GAUGE Willis F. Moore, Springfield, Vt, assignor to Bryant Chucking Grinder Company, Springfield, Vt., a corporation of Vermont Application March 31, 1942, Serial No. 436,935

1 Claim.

This invention relates to size gauges and has for an object to provide a gauge of simple construction but consistently capable of high accuracy and easily adjustable to measure work of different sizes.

For a complete understanding of this invention, reference may be had to the accompanying drawing in which Figure 1 is a top plan view of a gauge embody ing the invention, the parts being in work gauging position.

Figure 2 is a section on line 2-2 of Figure 1, but showing the indicator in full lines.

Figure 3 is an end elevation of the gauge looking toward the left in Figures 1 and 2.

Figure 4 is a view similar to a portion of Figure 2, but to a larger scale and with the gauging arm in idle position.

Figures 5 and 6 are detail sections on lines 55 and 66, respectively, of Figure 2.

Referring to the construction shown at I is indicated a support which is shown in the form of a rectangular platform. Extending lengthwise of this support is a T slot 2 forming a way. Within this way is adjustably supported a slide 3 shown as projecting above the way and being provided with a pair of spaced gauging elements 4 which make contact with a work piece 5 to be gauged. As shown this gauge is an internal gauge, but it is evident that by the use of appropriate gauging elements it might be an external gauge.

As shown the way 2 does not extend for the full length of the support I, but terminates short of one end thereof at an opening 6 extending through the support. Through this opening extends a short arm 1 of a lever 8. This short arm extends above the support I and carries a single gauging element 9 which cooperates with the two fixed gauging elements 4 of the adjustable slide 3. This lever 8, as best shown in Figures 2 and 6 has secured thereto a laterally extending bar In having two angularly related faces II and [2, as shown these faces being arranged substantially at right angles to each other. Secured to the face II is a pair of leaf springs l4 spaced laterally from the lever 8 substantially at the outer ends of the member If]. These springs l4 extend backwardly from the member I0 and as shown are secured to the under face of the support I. Adjacent to these springs I4, similar springs l6 are secured to the face 82 of the member l0, and these springs iii are upwardly extended and secured to the upright face I! of the support A. This upright face I! is also substantially at right angles to the lower face 18 to which the springs I4 are secured. These springs together form a fulcrum for the lever 8 having a center of oscillation substantially in line with the intersecting planes of the springs l4 and I5, but as these springs are fixed rigidly to their supporting parts, this fulcrum has no lost motion whatever as would be the case were a journal pivot employed.

The leaf springs are so arranged that the long arm 20 of the lever 8 is pressed thereby against a stop screw 3!] adjustable in the support i, the lever 8 then being in the position of Figure 4. It will be noted that the springs l4 and I6 constitute the sole spring means tending to press the lever against the stop screw. This is of great importance for high accuracy of gauging, as if it be attempted to engage one of the arms of the lever by a spring, a variable deflection of the lever arm is produced under shock applied by the work to the gauging lever when the gauge is applied to the work or the work is applied to the gauge which greatly impairs gauging accuracy, especially when measuring fractions of ten thousandths of an inch is necessary. Against the rear end portion of the arm 20 of the lever 8 there is in engagement therewith an actuating rod 2! of a position indicator 22 of conventional form. This position indicator is provided with a casing 23 having a T foot 24 which also engages in the way 2, and it may be secured in adjusted position along this way as by the two screws 25. This adjustment is for the purpose of adjusting the relative lengths of the effective lever arms accurately, correcting for manufacturing variations and wear. By maintaining this ratio constant, temperature changes of the lever do not affect the gauging accuracy. In order that the indicator dial will show the null or zero position when the size is correct so that variations from this desired size, either plus or minus, will be shown by departures of the indicator on one or the other side of the zero position, corresponding in amount to the amount of error of the size of the work piece, a standard size piece or master gauge is placed in gauging relation to the gauge and the dial of the gauge is turned as may be necessary to give the null or zero reading.

The gauge as thus constructed may be supported on a bench provided with a slot for receiving the portions which project below the support I, or, if desired, this support I may be mounted on legs (not shown) on a bench or other suitable support.

From the foregoing description of certain embodiments of this invention, it should be evident to those skilled in the art that various changes and modifications might be made without departing from the spirit or scope of this. invention as defined by the appended claim.

I claim: V

A gauge comprising a support having a way therein, a gauge element adjustable along said way, means for securing said element in fixed position, a, lever fulcrumed on said support and having a pair of arms, a gauge element carried by one of said arms cooperating with said adjustable gauge element to gauge work, an indicator in operative engagement with the other arm of said lever, and a support for said indicator adjustably fixed in said way.

WILLIS F. MOORE. 

